﻿using System;
//Write a program that calculates N!*K! / (K-N)! for given N and K (1<N<K).

class Factorials
{
    static void Main()
    {
        int n = 3;
        int k = 6;
        decimal kFact = 1;
        decimal nFact = 1;
        for (int i = k; i > (k - n); i--)
        {
            kFact *= i;
        }
        for (int i = n; i > 0; i--)
        {
            nFact *= i;
        }
        Console.WriteLine("N!*K! / (K-N)! = {0}", kFact * nFact);
    }
}

